Environment: In the blink of an eye, by geological time standards, we are engaging in an experiment which could return our planet to the atmospheric conditions that existed 50 million years ago, when crocodiles patrolled the warm water swamps of Greenland.
It is strange, then, that the story of global warming still seems to be leaving people cold.
The science that supports the story is certainly dramatic enough.
We know that the level of CO2 in our atmosphere remained below 300 parts per million (ppm) for the last 400,000 years and that in that time, small variations in the level of CO2 coincided with the regular advance and retreat of the ice ages. After 150 years of burning coal, oil and gas, the level has risen to 370 ppm and if we keep on our current course it will be closer to 1,000 ppm by the end of the century, bringing us back to the type of atmospheric conditions mentioned above.
Global temperatures have already started to rise in response to this increase in CO2.
Some of the most conclusive evidence showing that the two trends are connected, comes from the analysis of ice core samples taken from glaciers high in the Andean mountains.
These same glaciers are also the stars in Mark Lynas's book on how global warming is already starting to adversely affect the people on our planet.
The author spent three years collating first-hand reports on floods in Britain, melting permafrost in Alaska, rising sea levels in the Pacific islands, dust clouds in China, and tropical storms in Florida.
Those raised on west of Ireland weather might look down their noses at some of the accounts of unusual winds and rains, but the story does take off when the author climbs high into the Cordillera Blanca mountains in Peru. He is armed with crumpled old photos of mountain glaciers, and his mission is to see how they might have changed due to global warming.
The human twist in the tale is that it was his father who took the pictures, some 20 years earlier, when leading a geological expedition in the same uncharted mountains.
Scientific reports can describe the glacial retreat that is occurring but they could never be as powerful as Lynas's before-and-after photographs, which show how such massive glaciers have vanished in such a short space of time.
The frightening prospect behind these images is that the city of Lima, which is located in an arid desert below the mountains, is completely dependent on the runoff from such glaciers for its water.
Surprisingly, the first catastrophes of global warming may be caused by river waters falling rather than sea levels rising.
If the current trend continues, within decades we could see the rivers in Lima running dry and the need for a mass evacuation of some 10 million citizens. The same prospect looms in other cities in Peru, Bolivia and Ecuador, and half a billion people in India and Pakistan could be in a similar predicament as the retreating glaciers in the Himalayas threaten the rivers running down into the sub-continent. The European Alps are thought to have lost half their glacial mass between 1850 and 1990 and the speed of retreat now appears to be accelerating.
Those who think that we could be toasting ourselves nicely while all this is going on should know that temperatures in the Arctic are rising at a much faster rate than elsewhere on the planet, which could release vast quantities of cold melt-water to push our Gulf Stream south. We could end up living in a warmer planet where our own little region bucks the global trend and new glaciers stretch down the Dodder and Liffey valleys.
The sources for Lynas's facts and figures are well laid out in the appendix to the book but it is in essence a work of human rather than scientific observation. In his last chapter, the author reports from recent international Kyoto conventions, where national governments again decided to ignore the best scientific advice as to what to do. The policy adopted by the Irish Government, to buy up carbon credits on the international market rather than trying to do anything about our own pollution, could easily turn campaigners to apocalyptic despair.
It is a credit to Lynas that he sticks to telling his story in a rational and still compelling manner.
He is also honest enough to admit that his own air miles in researching the book blew some 20 years' worth of his own sustainable carbon quota. However, we badly need books like this to give us a sense of where our collective interest lies and to shake us out of our carbon-burning ways.
His book provides an excellent introduction to what will be a very big story.
• Eamon Ryan is a Green Party TD, representing Dublin South